Replace broken links of UC Berkeley videos with working ones from archive.org

Author: hiSandy

README.md

@@ -500,8 +500,8 @@ Write code on a whiteboard or paper, not a computer. Test with some sample input
 - [ ] [A Gentle Introduction to Algorithm Complexity Analysis](http://discrete.gr/complexity/)
 - [ ] [Orders of Growth (video)](https://class.coursera.org/algorithmicthink1-004/lecture/59)
 - [ ] [Asymptotics (video)](https://class.coursera.org/algorithmicthink1-004/lecture/61)
-- [ ] ~~[UC Berkeley Big O (video)](https://youtu.be/VIS4YDpuP98)~~
-- [ ] ~~[UC Berkeley Big Omega (video)](https://youtu.be/ca3e7UVmeUc)~~
+- [ ] [UC Berkeley Big O (video)](https://archive.org/details/ucberkeley_webcast_VIS4YDpuP98)
+- [ ] [UC Berkeley Big Omega (video)](https://archive.org/details/ucberkeley_webcast_ca3e7UVmeUc)
 - [ ] [Amortized Analysis (video)](https://www.youtube.com/watch?v=B3SpQZaAZP4&index=10&list=PL1BaGV1cIH4UhkL8a9bJGG356covJ76qN)
 - [ ] [Illustrating "Big O" (video)](https://class.coursera.org/algorithmicthink1-004/lecture/63)
 - [ ] TopCoder (includes recurrence relations and master theorem):
@@ -519,7 +519,7 @@ Write code on a whiteboard or paper, not a computer. Test with some sample input
     - Implement an automatically resizing vector.
     - [ ] Description:
         - [Arrays (video)](https://www.coursera.org/learn/data-structures/lecture/OsBSF/arrays)
-        - ~~[UCBerkley CS61B - Linear and Multi-Dim Arrays (video)](https://youtu.be/Wp8oiO_CZZE?t=15m32s)~~
+        - [UC Berkeley CS61B - Linear and Multi-Dim Arrays (video)](https://archive.org/details/ucberkeley_webcast_Wp8oiO_CZZE) (Start watching from 15m 32s)
         - [Basic Arrays (video)](https://www.lynda.com/Developer-Programming-Foundations-tutorials/Basic-arrays/149042/177104-4.html)
         - [Multi-dim (video)](https://www.lynda.com/Developer-Programming-Foundations-tutorials/Multidimensional-arrays/149042/177105-4.html)
         - [Dynamic Arrays (video)](https://www.coursera.org/learn/data-structures/lecture/EwbnV/dynamic-arrays)